New motor old prop?

[Permit53]

I have finally thrown in the towel and purchased a new O/B 2012 Suzuki 70hp four stroke. My previous engine was a 2001 DF70 Suzuki. I am curious if I am able to use my old prop? I do not know the manufacture, however stamped on the prop is 13-1/4X18 and it is stainless steal. Also I have tried to slide on the prop, but it will not fit. The shaft on my new motor is larger so I figure I can get a new hub with a larger dia to fit over the new propeller shaft? The back back spacer is also different in that it has a tab on the outside. Thank you for any help.

[boats.net]

Better to get new prop instead of retro fitting old one.

[Permit53]

I know that prop hubs get replaced from time to time so why would replacing one with a larger diameter opening be negative? thanks for your input.

[seaox230c]

Usually, the four strokes put out more torque than the 2 strokes so they are geared differently. The shaft output rotation is probably less than on the 2 stroke so you need more pitch or a larger dia or both to match the engine power curves. The old prop will function but crappy performance. A good used or new prop on ebay is 100-200 bucks...you just blew 4000 on a motor , why skimp on a mismatched prop

[Permit53]

Agreed, but the older engine was also a four storke.

[seaox230c]

Check the specs for your new motor...if a prop with your dimensions is a standard option...then just get it rehubbed. Make sure that they make a thrust washer that fits your old prop

[Permit53]

Here is the difference between the two propeller spacers and the new one on the right has a tab, but for what reason? I would think this would throw off the balance when the prop is spinning. Any ideas?

[Permit53]

Just wanted to update anyone who was interested... I got the prop re-hubbed and it runs within the proper rpm's I am one happy guy.